A two-stage algorithm for vehicle routing problem with timed-path in disaster response

In this paper we consider a vehicle routing problem with timed-path (VRPTP), which describes a distribution situation for post-disaster response. This problem is of great important for emergency rescue logistics. It is convenience for emergency rescue managers to find the distribution schemes in post-disaster. Our aim is to minimize the total travel distance while satisfying the demand of serviced disaster areas. To solve this problem, we develop a two-stage algorithm. The first stage of algorithm is the improved Floyd algorithm, which reduces the computational complexity of the Floyd algorithm by defining the disaster area model as an incomplete and undirected graph. We use the improved Floyd algorithm to find the optimal paths of any two serviced disaster areas. In the second stage of algorithm is the genetic algorithm, which determines the delivery order of serviced disaster areas. Combining the two stages, the solution of VRPTP is generated. Simulation results show the effectiveness of our method.